20. A: Why are you yawning?
B: I'm sleepy.
A: Why don't you go to bed?
B: I want to watch this TV show.
A: Maybe you should record it.
B: The tape recorder is broken.
A: Then you should watch the rerun.
B: Why? I'm watching the original.
A: But you'll be asleep in about one minute.
B: I'm just yawning because the commercials are on.
A: Okay. I'll tell you how the show ends.
B: Zzz. 0.6